Evaluation of the Ni Diffusion to the Surface of Au Plating for Soldering Process Control

摘要

One of the factors inhibiting the soldering on an Au electrode is that the underlying metal diffuses onto the surface of Au electrodes and an oxide layer is formed. In order to prevent any faults, the evaluation method of the underlying metal diffusion was examined. Usually, surface analytical techniques such as Auger electron spectroscopy and X-ray photoelectron spectroscopy are used for the evaluation of the underlying metal diffusion; however, a more rapid method is required for process management. We examined the measurement of the diffused underlying metal by energy dispersive X-ray spectroscope equipped to a low voltage scanning electron microscopy (SEM-EDX). It is possible to evaluate the underlying metal diffusion without detecting the underlayer signal by using SEM-EDX. It is suggested that measurements of the diffused underlying metal with SEM-EDX can be applied to the process management.